U.  S.  DEPARTMENT  OF  AGRICUL 

BUREAU  OF  ENTOMOLOGY— BULLETIN  No.  tf . 

L.    O.    HOWARD,    Entomologist. 


REPORT 


OX  THE 


HABITS  OF  THE  KELEP,  OR  GUATEMALAN 
COTTON-BOLL-WEEVIL  ANT. 


By    O.   F.    COOK, 

Botanist  in  Charge  of  Investigations  in  Tropical  Agriculture, 
Bureau  of  Plant  Indnsfru. 


WASHINGTON: 

GOVERNMENT    PRINTING    OFFICER. 
1904. 


BUREAU  OF  ENTOMOLOGY. 

I..  0.  Howard,  Entomologist  and  Chief  of  Bureau. 

.  ,  rirm  nlcU  field  work. 
I.  II    Chittenden,  in  charge  of  breeding  experiments. 
A    D.  Hopkins,  in  charge  of  forest  insect  investigations. 
\\    I ».  Hunter,  in  charge  of  cotton  boll  weevil  investigations. 

..  in  charge  of  apicultural  investigations. 
1\  M.  Webster,  in  charge  of  field-crop,  insect  investigations, 
A    I  .  Qi  aintance,  in  charge  of  bollworm  investigations. 

BWARZ,     D.    W.     CoQUILLETT,     Til.     PERGANDE,     XaTFTAN     BaNKs. 

I         Clifton,  E.  s.  <;.  Titus,  F.  C.  Pratt,  August  Busck,  Otto  Heidemann, 
Caudell,  J.  Kottnsky,  R.  P.  Currie,  F.  D.  Couden,  Assistants. 

I     I  .  A.LTBOU8E,  W.  1     Tastet,  Mary  <  \.  Champney,  A.  J.  Leister,  D.J.  Parti 
T.  A.  Kki.khf.k.  Stenographers  and  Clerk*. 

Lillian  L.  Howenstein,  J.  P.Strauss,  Drafstmen. 

G.  II.  Harris,  W.  E.    Hinds,  A.  W.  Morrill,  Springer  Goes,  C.  M.  Wai 

wford,  Jr.,  W.  A.  Hooker,  W.  W.  Yothers,   A.  ('.   Morgan,  W.  D.  Pierce, 
I     D.  Sanderson,  E.  C.  Sanborn,  A.  ('.  Lewis,  A.  F.  Conradi,  H.  A.  Mob 
S    I     Mc<  LENDON,  E.  s.   Hardy,  R.  ('.  Howell,  A.  W.  Buckner,  J.  B.  Garrett, 
4ton  boll  weevil  investigations. 
I     i      Bishopp,  C.  T.  Brues,  A.  A.  Girault,  C.  R.  Jones,  engaged  in  bollm 

gati 
.1.  L  Webb,  II.  K.  Burke,  W.  I".  Fiske,  engaged  inforesi  insect  investigatio 

IE  Martin,  J.  M.  Rankin,  engaged  in  apicultural  investigations. 
Henrietta  A.  Kelly,  C.  J.  Gillies,  W.  A.  Keleher,  Marie  Key.  Mabel  1    i 

bet  OiBOBN,  J.  s.  Hine,  (J.  F.  CiiAMBLiss,  Lawrence  Bruner,  Temporary 

Ayt 


U.  S.   DEPARTMENT  OF  AGRICULTURE, 

BUREAU  OF  ENTOMOLOGY— BULLETIN  No.  49. 

L.    O.    HOWARD,    Entomologist. 


REPORT 


ON  THE 


HABITS  OF  THE  KELEP,  OR  GUATEMALAN 
COTTON-BOLL-WEEflL  ANT. 


By    (  ).    F.    (  1(  )OJv, 

Botanist  in  Chargi  of  Investigations  in  Tropical  Agriculture, 
Bureau  of  Plant  Industry. 


WASHINGTON: 

GOVERNMENT     PRINTING     OFFICE, 

1904. 


LETTER  OF  TRANSMITTAL. 


U.  S.  Department  of  Agriculture, 

Bureau  of  Entomology, 
Waskmgton,  I).  ('..  July  ,J0\  190^. 
Sir:  I  have  the  honor  to  transmit  herewith  for  publication  an 
account  of  the  habits  of  the  so-called  Jeelep,  or  Guatemalan  cotton- 
boll-weevil  ant,  prepared  by  Mr.  O.  F.  Cook,  and  submitted  to  this 
Bureau  by  the  Chief  of  the  Bureau  of  Plant  Industry  for  the  reasons 
given  in  the  subjoined  letter.  The  desirability  of  publishing  these 
facts  at  once  is  obvious,  in  spite  of  the  fact  that  the  ant  has  not  as  yet 
been  classified.  The  establishment  of  the  colonies  under  proper  super- 
vision in  Texas  is  now  going  on,  and  a  careful,  s}^stematic,  and  bio- 
logic study  will  be  made  by  Mr.  Cook  with  a  corps  of  expert  assistants. 
The  full  life  history  and  systematic  relationships  of  the  ant  will  be 
treated  in  a  later  publication. 

I  recommend  the  publication  of  this  paper  as  Bulletin  No.  49,  of 
this  Bureau. 

Respectfully.  L.  ().  Howard, 

Entomologist. 
lion.  James  Wilson, 

Sco/'ckit-y  of  Agriculture. 


United  State*  Department  of  Agriculture, 
Bureau  of  Plant  Industry,  Office  of  Chief  of  Bureau, 

Washington,  1).  C.  July  ..'<;,  1904. 
Dear  Sir:  On  May  27  last  there  was  published  in  Report  Xo.  78  from  the  Secre- 
tary's office  an  article  by  Mr.  0.  F.Cook,  of  this  Bureau,  on  "An  Enemy  of  the 
Cotton  Boll  Weevil."  Since  this  publication  the  enemy  of  the  weevil  discovered  by 
Mr.  Cook,  namely,  an  ant  from  Guatemala,  has  been  introduced  into  Texas.  Mr. 
Cook,  in  cooperation  with  the  officers  of  your  Bureau,  is  now  making  special  studies 
of  the  ant  in  Texas,  and  lias  submitted  a  further  statement  upon  its  habits.  Popular 
interest  in  the  ant  has  resulted  in  the  circulation  of  many  fanciful  statements,  some 
of  which  have  aroused  doubts  regarding  the  desirability  of  introducing  it  into  the 
United  States.  So  widespread  is  the  demand  for  further  information  upon  the  ant 
that  the  publication  of  some  of  the  pertinent  facts  regarding  its  habits  would  seem 
to  be  in  order.  In  view  of  the  fact  that  arrangements  are  now  being  made  for  all 
future  work  on  the  ant  to  be  carried  on  under  the  direction  of  the  Bureau  of  Ento- 
mology, I  would  respectfully  suggest  the  immediate  publication  of  the  accompanying 
manuscript  of  Mr.  Cook  as  a  bulletin  from  your  Bureau. 

Respectfully,  B.  T.  Galloway, 

( It  it  f  of  Bun  mi . 
Dr.  L.  ().  Howard, 

Chief  Bureau  of  Entomology. 


HABITS  OF  THE  KELEP,  OR  GUATEMALAN  COTTON- 
BOLL-WEEVIL  ANT. 


The  kelep0  was  discovered  on  the  cotton  April  20,  100-L.  in  Alta 
Vera  Paz,  Guatemala,  and  its  efficiency  as  a  destroyer  of  the  Mexican 

cotton  boll  weevil  (Anthonomus  grandis  Boh.)  was  demonstrated  the 
following  day.  It  was  immediately  appreciated,  of  course,  that  such 
an  insect  would  be  of  value  in  Texas,  providing  that  it  could  be  colo- 
nized and  would  thrive  in  that  State,  and  that  it  had  no  noxions  habits. 
To  the  solution  of  these  questions  all  subsequent  study  of  the  species 
has  been  directed. 

Immediate  practical  use  was  also  made  of  these  observations  of 
habits  and  life  history.  The  ant  has  been  brought  to  Texas  in  healthy, 
vigorous  condition,  notwithstanding  injunction  proceedings  and  other 
unavoidable  delays,  which  lengthened  the  period  of  travel  and  cap- 
tivity to  more  than  a  month.  Of  about  4.000  ants,  in  89  colonies, 
scarcely  more  than  a  dozen  died  during  the  voyage,  and  half  of  these 
were  in  a  single  colony  which  was  for  a  time  deprived  of  a  queen. 
The  loss.  too.  was  made  good  many  times  over  by  the  emergence  dur- 
ing the  voyage  of  numerous  ants  from  pupae  which  had  been  collected 
and  placed  in  the  cages  with  the  mature  insects. 

AVhile  the  adult  worker  ants  expose  themselves  freely  to  dry  air  and 
sunlight,  the  chief  factor  in  the  successful  transportation  of  the  colonies 
has  been  the  maintenance  of  adequate  moisture  in  the  cages  by  means 
of  artificial  nests  constructed  of  earth  and  stones,  carefully  built  in  to 
form  underground  chambers  not  to  be  shaken  down  by  the  jarring 
unavoidable  in  steamboat  and  railroad  travel.  It  was  fortunate, 
perhaps,  that  the  weevil  ant  was  quite  unknown  when  we  left  the 
United  States,  for  our  outfit  included  nothing  in  the  way  of  bell  jars, 
glass  plates,  and  other  laboratory  appliances  recommended  by  Lubbock 
and  other  investigators  of  ants.  Much  time  might  have  been  wasted 
with  these  complicated  contrivances  which  would  at  best  have  been 
far  less  suited  to  our  purposes  than  the  very  simple  means  to  which 
necessity  compelled   a   resort.     For  this  ant.  at  least,  the  stone  and 

"This  is  the  name  of  the  cotton-protecting  ant  in  the  Kekchi  language  of  Alta  Vera 
Paz,  ( iuatemala.  The  word  has  no  other  meaning  or  derivation,  but  appears  to  have 
come  down  from  ancient  times,  when  a  higher  agricultural  civilization  existed  in  this 
region  than  that  found  by  the  Spaniards.  The  accent  is  on  the  second  syllable,  and 
the  first  sounds  as  though  written  hay. 


earth  nests  built  nt  the  bottom  of  glass  jars,  with  the  lower  half  pro- 
tected from  the  light  by  closely  wrapped  (hick  paper,  and  closed  above 
i-\  b  piece  of  cloth,  leave  little  to  be  desired.  Many  of  the  colonies 
adopted  the  artificial  nests  without  change,  or  have  even  carried  out 
the  few  particles  of  earth  which  accidentally  fell  in  while  the  chambers 
were  being  constructed  for  them.  Others  have  brought  in  earth  and 
remodeled  their  apartments  and  are  now  living  in  chambers  of  practi- 
cally the  same  size  and  shape  as  in  their  own  nests.  They  have  ceased 
t<>  he  disturbed  by  the  occasional  removal  of  the  paper  cup  from  the 
bottom  of  their  cage,  and  all  the  operations  of  the  colonies  can  be 
observed  under  conditions  altogether  favorable. 

It  is  not  intended,  however,  to  enter  at  this  time  upon  detailed 
accounts  of  the  interesting  domestic  behavior  of  the  ants,  but  rather 
to  give  what  might  be  called  a  biological  outline  of  their  activities, 
from  which  it  may  be  possible  to  understand  something  of  their  place 
in  nature  and  of  their  probable  utility  in  agriculture. 

One  of  several  minor  agricultural  virtues  of  these  ants  lies  in  the 
fact  that  they  digno  large  chambers  or  passages  which  can  serve  as 
pitfalls  for  men  or  farm  animals,  as  do  many  other  kinds,  including 
the  leaf-cutting  ant  of  southern  Texas,  which  the  cotton  planters  are 
attempting  to  exterminate  at  much  expense.  The  nest  of  the  kelep  is 
a  simple  burrow,  extending  from  1  to  3  feet  into  the  ground,  and  con- 
sists of  from  three  to  six  small  chambers,  with  connecting  galleries. 
The  passageways  are  about  a  quarter  of  an  inch  in  diameter  and  the 
chambers  from  1  to  :\  inches  broad  and  half  or  three-fourths  of  an  inch 
high,  with  level  or  slightly  sloping  floors  and  broadly  arched  roofs. 
The  queen,  with  some  of  the  eggs  and  younger  larvae,  is  generally  to 
be  found  in  the  lowest  chamber,  but  the  pupae  in  their  cocoons  are 
usually  near  the  top  and  the  remainder  of  the  smaller  larva1  and  i 
lower  down.  1 1 1  addition  to  tin4  chambers  inhabited  by  the  ants  there 
are  in  each  nest  one  or  more  cavities  for  the  storage  of  the  hard  parts 
the  bone-.  (l-  it  w  ere  of  the  insects  which  the  colony  has  captured 
and  eaten.  Head-,  legs,  wings,  and  other  fragments  of  insects  of 
many  kinds,  including  the  boll  weevil,  are  here  packed  indiscrimi- 
nately together.  The  mass  is  often  penetrated  by  a  network  of  deli- 
cate root-,  and  is  the  home  of  several  small  animals  which  commonly 
find  shelter  in  the  nests  of  the  keleps:  a  snail,  a  worm,  a  mite,  a  Pod- 
lirid,  and  a  thysanuran.  A  h\  menopterous  insect  was  also  obtained. 
which  i-  probably  a  parasite  of  the  ants. 

The  habit  of  preserving  this  useless  debris  is  rendered  the  more 
curious  by  the  fa«t  that  dead  ants  seem  not  to  he  included  in  the  col- 
lection, but  are  carried  out  of  the  nest,  as  is  the  general  custom 
among  bees  and  other  related  insects.  It  was  thought  at  one  tune 
that  -<»ine  of  the  captive  colonics  were  resorting  to  cannibalism,  since 
omc  dead  ant-  were  found  pulled  in  pieces  like  the  insects  which  had 


been  eaten,  but  this  may  have  resulted  from  the  prolonged  efforts  of 
the  living  ants  to  carry  the  dead  out  of  the  nests.  When  the  insects 
were  being  liberated  at  Victoria  after  a  month  of  captivity,  almost 
the  first  thing  they  did  was  to  bring  out  their  dead  ants  and  carry 
them  as  far  from  their  nests  as  the  boundaries  of  their  inclosures 
would  permit. 

The  extremely  slight  mortality  of  the  ant-  during  the  journey  is  an 
evidence,  certainly,  of  considerable  hardiness.  The  unexpectedly 
good  result  was  probably  due  also,  in  a  measure,  to  the  fact  that  the 
insects  were  transported  during  the  rainy  -eason  when  the  atmos- 
pheric humidity  was  high  and  the  soil  in  the  cages  did  not  dry  out 
rapidly.  The  margin  of  safety  is  evidently  a  rather  narrow  one.  If  the 
-oil  i-  too  wet  the  insects  forsake  their  chambers  and  crowd  together 
at  the  surface.  When  this  was  noticed  the  cloth  covers  were  removed 
to  give  more  air  and  permit  more  rapid  evaporation.  Too  great  dry- 
ness, however,  is  a  much  more  serious  danger.  Unless  the  color  of 
the  -oil  be  carefully  watched  the  first  intimation  of  difficult}*  is  likely 
>me  in  the  form  of  dead  ants.  The  danger  could  be  lessened,  of 
course,  by  increasing  the  quantity  of  soil  in  the  cages,  but  this  would 
have  the  disadvantage  of  additional  bulk  and  weight,  important  con- 
siderations  where  transportation  is  so  difficult  as  in  Guatemala. 

It  seemed  possible  when  the  first  report  was  sent  in.  that  the  very 
limited  distribution  of  the  ants  might  be  due  to  some  inability  on 
their  part  to  dig  in  other  than  the  very  loose  shale  soil  which  covers 
the  particular  slopes  specially  preferred  by  the  insects,  according  to 
the  belief  of  the  Indians.  Later,  however,  the  ants  were  found  in 
somewhat  different  situations,  and  even  on  level  bottom  lands,  though 
such  are  very  rare  in  that  part  of  Guatemala.  Considerable  diver- 
sity of  -oil  was  also  revealed  during  the  excavations  made  in  cap- 
turing the  colonies  brought  to  the  United  States.  Furthermore, 
another  way  was  found  of  explaining  why  the  ants  have  so  limited 
a  range.  It  is  only  on  these  very  loose  soils  that  weeds  can  be 
pulled  easily,  and  hence  it  is  only  these  which  can  be  cleared  without 
burning.  A  nearly  continuous  cultivation  can  be  maintained,  which 
i-  very  exceptional  under  Indian  methods  of  agriculture.  The  cotton 
is  planted,  too.  during  the  latter  half  of  October — a  very  rainy  period 
when  burning  is  impracticable,  so  that  the  ants  are  not  destroyed,  as 
must  happen  in  the  clearing  of  land  for  corn,  beans,  and  other  crop-. 
If  these  considerations  have  the  supposed  bearing,  it  i-  not  impossi- 
ble that  in  the  United  States,  where  the  land  is  cultivated  more  con- 
tinuously, the  ant-  may  multiply  and  extend  their  boundaries  much 
more  rapidly  than  they  have  been  able  to  do  in  Guatemala. 

Every  practicable  effort  was  made  in  Guatemala  to  rind  the  ant-  in 
other  localities  more  accessible  than  the  remote  and  mountainous  dis- 
trict where  they  were  first  discovered  and  from  which  the  caged  insects 


had  to  be  brought  out  by  Indian  carriers.  None  of  the  keleps  were 
found,  however,  in  other  parts  <>f  the  country,  and  the  probability  of 
their  existence  elseia  here  seems  small  in  view  of  the  fact  that  no  other 
field  cultures  of  cotton  exist  in  the  neighboring  regions,  although  the 
natural  conditions  are  generally  favorable  and  many  attempts  have  been 
made,  some  on  a  very  large  scale.  In  a  few  instances  a  satisfactory 
crop  was  obtained  the  first  year  before  the  weevils  had  time  to  multi- 
ply, and  expectations  were  aroused  which  only  deepened  the  subse- 
quent disappointment.  One  very  small  field  of  cotton  in  the  Polochic 
Valley,  below  Tucuru,  was  said  to  be  4  miles  from  any  other  plant-. 
but  the  weevils  had  found  it  before  the  crop  ripened.  There  are 
rumors  of  the  existence,  in  Mexico,  of  tree  cotton-  which  are  resistant 
to  the  boll  weevil,  hut  in  Guatemala  these  suffer  quite  as  much  a^  the 
smaller  kinds.  .  Large  trees  often  failed  to  furnish  a  single  uninjured 
boll  as  a  specimen  for  our  collection  of  varieties.  The  wish  to  find 
the  protecting  insects  nearer  home  has  been  echoed  l>v  many  new-- 
paper  account-  claiming  tin4  existence  of  the  same  or  similarly  useful 
ants  in  various  parts  of  Texas,  hut  thus  far  none  of  these  reports  has 
proved  to  he  based  on  fact.  The  kelep  is  as  yet  the  only  ant  known 
to  attack  and  destroy  healthy  adult  boll  weevils,  just  as  the  cotton 
grown  with  the  protection  of  the  ants  is,  so  far  as  known.  the  only 
field  culture  permanently  maintained  in  the  weevil-infested  regions  of 
( Vntral  America. 

It  was  feared  at  first  that  the  keleps  would  not  be  able  to  excavate 
nests  in  other  than  very  loose  and  granular  soils,  and  particularly  that 
they  might  fail  to  penetrate  hard  and  tenacious  subsoils  like  those 
which  underlie  some  of  the  cotton  fields  about  Victoria.  It  seems,  how- 
ever, that  these  offer  no  special  difficulties  for  the  ants.  Some  of  the 
buried  colonies  are  bringing  up  earth  from  a  depth  of  about  L8  inches, 
and  in  experimental  nests  constructed  of  the  tough  Texas  soil  the  ants 
have  given  ocular  demonstration  of  their  power  to  dig  out  passage- 
ways. The  nr-t  of  a  colony  which  has  been  in  the  ground  at  Victoria 
for  a  week"  -how-,  on  being  dug  out,  a  nearly  vertical  gallery,  with  a 
depth  of  1  I  inches,  and  the  usual  lateral  chambers.  Whether  the  ants 
will  survive  the  floods  to  which  many  of  the  level  cotton  land-  of 
Texas  are  subject,  is  <>ne  of  the  questions  still  to  be  answe'red.  In 
Guatemala  they  are  accustomed  to  very  heavy  rains  which  thoroughly 
saturate  the  -oil.  but  the  drainage  is  excellent.  Possibly,  however, 
the  impervious  nature  of  some  of  the  Texas  subsoils  may  afford  pro- 
tection by  holding  air  in  the  nests. 

Another  equally  practical  question  is  frequently  asked  by  planters 
who  call  to  see  the  ant-.     Will   not  plowing  and  cultivation  destroy 
the    nests    and    drive    the    insects    from    the    cotton    fields 3      A-    the) 
burrow    to   a    depth    of    from    I    to    .*'.    feet,    the    -hallow    plowing  eu- 
tonmn   in  Texan  will  cut  oil  onl\  the  passage  leading  to  the  surface, 


and  this  the  ants  will  undoubtedly  be  able  to   renew  in  a  few  hours. 

No  injury  need  be  anticipated  on  this  score,  except  the4  loss  of  the  few 
individuals  actually  stepped  on  and  crushed.  Where  the  surface  soil 
is  loose  the  ants  are  careful  to  start  their  nests  against  some  rig-id 
object,  often  at  the  base  of  the  cotton  plant  itself,  and  follow  the 
root  down  "2  or  3  inches  where  a  more  moist  and  firm  material  can  be 
reached.  The  frequency  with  which  this  occurred  in  Guatemala  may 
indicate  that  the  ants  transfer  their  nests  to  the  vicinity  of  the  cotton 
after  it  has  begun  to  grow.  There  was  no  indication  that  the  making 
of  the  burrows  injured  the  plants,  but,  if  anything,  the  reverse:  at 
least  the  largest  ant  colonies  were  dug  out  where  the  cotton  had  flour- 
ished best.  General  reasoning  would  also  suggest  that  the  slight  open- 
ing of  the  soil  about  the  plant  would  be  as  likely  to  benefit  as  to  injure 
it.  Nothing  was  found  to  indicate  that  the  roots  of  the  cotton  or  any 
other  plant  are  attacked  by  the  ants.  They  may  gnaw  off  a  small  root 
which  interferes  with  their  operations,  but  they  disturb  the  soil  so  little 
that  such  damage  must  certainly  be  extremely  slight  and  in  complete 
contrast  to  the  extensive  injuries  often  done  by  the  large  red  ants 
(Pogonomymnex  barbatus)  native  in  Texas,  which  permit  nothing  to 
grow  within  an  area  of  several  square  yards  surrounding  the  entrance 
of  their  nest. 

Like  the  human  inhabitants  of  tropical  countries,  the  ants  have  the 
habit  of  taking  a  siesta.  When  the  weather  is  clear  and  hot  they  are 
much  less  numerous  upon  the  cotton  plants  in  the  middle  of  the  day 
than  in  the  morning  or  evening,  and  in  the  longer  days  and  drier 
climate  of  Victoria  a  tendency  to  lengthen  this  period  of  retirement 
to  the  underground  nest  is  already  evident.  That  the  strong  sunlight 
and  heat  are  distasteful  to  the  ants  is  easily  proved  by  alternately 
shading  and  exposing  the  entrance  of  the  nest.  The  ants  appear 
promptly  when  there  is  shade  and  seek  their  subterranean  shelter 
when  it  is  withdrawn.  The  fact  that  the  ants  are  thus  quiescent  in 
the  middle  of  the  day  when,  according  to  Messrs.  Hunter  and  Hinds, 
most  of  the  weevil  injuries  are  inflicted,  might  seem  to  interfere  with 
their  utility.  But  apart  from  the  poetic  justice  of  having  the  weevil 
caught  in  the  act  of  damaging  the  cotton,  all  purposes  would  be  served 
as  well  or  better  if  it  were  disposed  of  in  the  evening  or  the  morning 
before.  It  seemed  in  Guatemala  that  the  weevils,  as  well  as  the  ants, 
were  more  numerous  in  the  earlier  and  later  hours  of  the  day;  at  least 
they  were  easier  to  find.  In  rainy  or  cloudy  weather  more  ants  remain 
on  the  cotton  during  the  day. 

The  cotton  which  they  protect  in  Guatemala  is  an  annual  variety. 
The  crop  is  harvested  in  May  and  the  old  plants  pulled  up  to  make 
room  for  the  development  of  peppers,  which  it  is  customary  to  plant 
among  the  cotton,  to  ripen  somewhat    later.     The  ants  very   rarely 


10 


climb  the  pepper  plants,  but  weevils  were  in  r  few  instances  found 
roosting  upon  them     a  wafer  place,  apparently,  than  upon  the  cotton. 

While  most  : 1 1 1 1  colonies  have  only  one  queen,  several  were  found 
with  larger  numbers,  usually  two  or  three,  but  in  one  case  six  and  in 
another  fifteen.  Queens  occasionally  retain  one  or  both  of  their  win  lis. 
and  when  the  colony  with  the  fifteen  queens  was  captured  several  of 
them  had  wings,  which  were  lost  later.  It  was  thought  that  these 
queens  might  be  young  and  unfertilized,  bul  large  numbers  of  eggs 
have  been  laid  and  these  are  now  hatching.  If  the  queens  were  unfer- 
tilized the  eggs  will  doubtless,  to  judge  from  the  analogy  of  bees  and 
other  ants,  produce  males,  which  may  )>c  very  desirable  if  it  should 
prove  possible  to  breed  the  insects  in  captivity. 

The  queen  does  not  have  a  special  chand»er.  bul  walks  about  among 
the  workers.  She  was  usually  found  in  the  lowest  chamber  of  the 
nest,  with  eggs  and  young  larvae,  and  nearest  bo  the  "bone  yard." 
hut  if  the  lower  chambers  of  the  nest  were  opened  first  hy  digging  in 
from  the  side,  -he  sometimes  took  refuge  in  the  upper  rooms  or  per- 
haps escaped  into  the  open  air.  In  several  of  the  nests  no  queens 
were  found.  In  the  cages  the  queens  usually  remain  constantly  in  the 
lowest  chambers  and  are  \\h\  by  the  workers.  Some  queens  seem. 
however,  to  have  more  of  the  instincts  of  workers,  and  one  or  two 
regularly  come  to  the  surface  to  feed  with  thorn.  In  one  instance  a 
worker  was  seen  carrying  a  queen  about  the  nest.  She  had  been 
seized  by  the  jaws  and  her  body  was  waving  in  the  air  over  the 
worker's  hack.  It  was  feared  at  first  that  she  was  dead,  hut  on  being 
released  her  actions  were  normal. 

At  Victoria  some  of  the  colonic-  were  released  by  placing  the  jar  on 
the  ground  and  inserting  a  bent  cotton  stalk  on  which  the  insects  could 
climb  out.  'They  immediately  began  digging  a  burrow  at  the  l>a-o  of 
the  adjacent  cotton  plant,  and  in  the  course  of  two  hours  the  workers 
were  ready  for  the  queen  and  a  delegation  of  two  or  three  of  them 
brought  her  out.  She  returned  several  times  to  the  underground 
chandlers  <»f  the  cage,  hut  was  finally  aroused  sufficiently  to  follow 
along  the  cotton  stalk  and  out  of  the  jar.  The  eggs  and  larva?  had 
already  been  removed.  One  of  the  queens  did  not  go  directly  into 
the  ground,  hut  climbed  the  cotton  plaid  and  remained  there  about  an 
hour,  in  -pite  of  many  \  risits  from  workers  who  caressed  herewith  their 
antenna1  :i-  though  to  coax  her  to  come  down.  In  some  instances  the 
queen  remained  longer  in  the  old  nest  and  was  not  transferred  till 
night,  when  the  colonies  seem  to  he  quite  as  active  as  in  the  daytime, 
perhaps  more  so.  On  another  occasion  the  queen  was  carried  bodily 
into  the  new  nest  by  a  worker  who  seized  her  by  the  mandibles,  as 
uient  ioncd  aho\  e. 

The  \ei\  strong  homing  instinct  of  the  ants  would  have  made  it 
i->  release  them  in  the  plantations  lot-  study,  even  if  their  other 


11 

habits  had  been  loss  known.  Instead  of  scattering  or  becoming  bewil- 
dered under  the  strange  conditions  they  act  from  the  first  as  though 
they  were  thoroughly  familiar  with  their  surroundings.  Many  colo- 
nies have  been  tested  on  a  table  isolated  below  by  water.  The  insects 
were  allowed  to  climb  out  of  their  cages  by  means  of  a  ladder  consist- 
ing of  a  cotton  leaf  with  the  stem  bent  back.  There  was  no  hesitation 
or  preliminary  exploration.  The  ants  tiled  out  at  once  and  spread 
themselves  over  the  table.  Weevils  were  often  caught,  stung,  and 
carried  back  to  the  cage  within  a  minute  or  two  after  the  release  of 
the  ants  from  their  captivity. 

All  observations  continue  to  confirm  the  previous  report,  that  this 
ant  is  a  truly  predaceous  insect.  Compared  with  the  nervous  haste 
of  many  other  species,  its  motions  arc  slow  and  deliberate,  and.  like 
the  so-called  praying  mantis,  it  stands  for  long  periods  quite  motion- 
less, with  its  antennae  and  mandibles  extended,  ready  for  something 
to  come  that  way  and  be  caught.  Jt  seldoms  attacks  weevils  or  other 
insects  unless  they  are  in  motion  and  a  weevil  is  generally  safe  as  long 
as  it  keeps  quite  still.  The  ant's  field  of  vision  seems  limited  to  less 
than  an  inch.  This,  however,  is  adequate  for  practical  purposes,  since 
the  most  convenient  time  for  catehine  the  weevil  is  when  it  is  climbing1 
up  the  plant.  In  Guatemala  a  weevil  placed  on  a  leaf  stem  so  as  to 
walk  up  and  meet  an  ant  was  almost  sure  to  be  taken.  In  that  coun- 
try, however,  weevils  are  seldom  or  never  seen  crawling  about  on  the 
cotton,  perhaps  because  the  ants  have  discouraged  this  habit;  but  Mr. 
Hunter  informs  me  that  in  Texas  the  weevils  frequently  reach  the 
bolls  by  climbing  up  from  the  ground,  and  that  they  usually  ]>a^< 
along  the  stems  from  one  square  or  boll  to  another,  so  that  the  oppor- 
tunities of  the  ants  are  excellent. 

That  the  ants  know  how  to  sting  the  weevils  at  the  only  two  points 
where  their  armor  is  vulnerable  shows,  of  course,  a  highly  specialized 
instinct,  and  it  is  altogether  likely  that  all  individuals  do  not  possess 
it  in  an  equal  degree.  Some  colonies,  too.  attack  the  weevils  much 
more  promptly  and  skillfully  than  others.  As  might  naturally  be 
expected,  hunger  increases  the  eagerness  and  adroitness  of  the  insects. 
and  it  seems,  too,  that  the  members  of  the  large  colonies  show  more 
ferocity  than  those  of  the  small,  as  is  known  to  be  the  case  with  the 
honey  bee  and  many  other  social  animals.  The  imported  colonies 
contain  from  twenty  to  one  hundred  and  ten  workers  each,  averaging 
between  forty  and  fifty.  It  may  be  that  the  smaller  communities  and 
their  queens  would  survive  in  captivity  as  long  or  longer  than  the 
larger  colonies,  but  if  it  should  appear  that  they  are  less  able  to  forage 
successfully  the  desired  increase  in  numbers  may  be  much  slower,  so 
that  the  use  of  larger  cages  and  the  bringing  of  larger  colonies  may 
prove  desirable,  should  further  importations  of  the  ants  be  made 
The  rate  of  propagation  of  the  keleps  is  likely  to  prove  much  slower 


12 

than  thai  <>f  tin'  weevil-,  hut    the  ants  are  such  long-lived    insects  that 

th-v  ma\  l»c  expected  to  overtake  the  weevils  under  favorable  con- 
dition-. An  ant  <|iicen  has  been  known  to  live  for  fifteen  years  and  a 
worker  for  six  \  ears. 

The  tad  that  th<-  ant-  attack,  paralyze,  and  destroy  the  weevils  has 
been  assumed  frequently  to  mean  that  a  battle  takes  place  between  the 
Insects,  and  pictures  of  such  imaginary  encounter-  have  appeared  in 

the    newspapers.       A-    a    matter   of    fact,    however,    the   weevil    has    no 

mean-  of  defense  except  its  armor  and  is  quite  at  the  mercy  of  any 
ant  strong  and  skillful  enough  to  sting  it.  Even  this  stinging  is  not 
always  necessary,  some  weevils  being  carried  into  the  nest  without 
being  stung,  and  perhaps  while  still  feigning  death  to  avoid  discovery. 
The  ant-  are  strong  enough  to  pull  the  weevil-  in  pieces,  hut  the  pre- 
liminary  sting  facilitates  matters  by  preventing  any  further  efforts  at 
escape.  It  i>  a  well-known  fact  that  insect-  and  spiders  which  have 
been  stungand  paralyzed  by  predaceous  wasps  as  food  for  their  young 
will  keep  for  considerable  periods.  The  ant-  may  utilize  this  means 
of  storing  food  when  there  is  an  overabundance;  a  colony  fed  for  the 
l;i-t  three  day-  exclusively  on  weevils  kills  more  than  it  consumes,  and 
piles  up  the  victims. 

The  fact  that  the  ant  uses  its  sting  in  capturing  its  prey  has  led 
some  to  confuse  it  with  the  stinging  ant-  which  are  serious  pests  in 
some  tropical  countries.  Some  of  these  inflict  painful  injuries  and  are 
much  feared.  There  is,  for  example,  an  ant  which  makes  nests  among 
the  leaves  of  the  coffee  t  rees  in  Liberia,  rendering  it  quite  impracticable 
ither  the  crop  until  the  insects  are  dislodged  by  fire.  The  kelep 
doe-  not  belong,  however,  to  any  such  category.  It  is  a  predaceous 
or  hunting  ant  which  very  seldom  stings  except  to  paralyze  its  prey 
and  thus  render  the  game  easier  to  capture  and  carry  off;  hut  at  other 
time-  it  has  no  inclination  to  sting  and  does  so  only  when  actually 
seized  <  r  injured.  The  sting,  however,  is  too  small  and  weak  to  pene- 
trate the  skin  of  the  inside  of  the  hand,  so  that  the  insects  can  he  picked 
up  w  it  h  entire  impunity.  I  f  accidentally  squeezed  between  the  fingers 
or  caught  under  one*-  collar,  a  kelep  may  he  able  to  sting,  hut  the 
wound  -mart-,  in  most  people,  for  only  a  few  minutes,  and  is  on  the 
w  hole  a  less  formidable  injury  than  a  mosquito  bite,  since  the  irritation 
i-  less  prolonged. 

It  should  be  a  sufficient  testimony  to  t ho  peaceable  temper  of  the 
ants  to  state  that  iii  opening  about  1»»«>  nests  and  collecting  some  4,000 
ant-  Mr.  I)oyle;uid  I  were  stung  only  about  half  ado/en  times,  and 
that  with  no  care  or  precautions.  A  majority  of  the  ants  were  picked 
up  w  ith  the  hare  hand-  while  the  disturbed  insects  craw  led  at  liberty 
over  H-.  Under  such  circumstances  a  stinging  ant  would  attempt 
t"  wound  any  foreign  object  which  came  in  its  way,  hut  the  keleps 
have  apparently    no   tendency    to  defend   their  nest   in   this  manner. 


13 

They  are  not  afraid  to  climb  upon  the  hand  if  one  stands  still,  but  they 

appear  to  do  this  out  of  curiosity,  and  not  to  fight;  and.  as  already 
stated,  they  never  attempt  to  sting  human  beings  unless  actually  held 
or  injured.  The  fear  that  they  may  interfere  with  the  cultivation 
of  the  cotton  or  with  the  harvesting  of  the  crop  is  entirely  ground- 
less. It  would  be  much  more  nearly  correct  to  compare  them  with  a 
harmless  insect-eating  animal  like  the  toad  than  with  the  vegetable- 
feeding,  stinging  ants,  like  the  large  red  ant  so  common  about  Victoria. 
This  latter  species  has  a  vicious  temper,  seeks  actively  to  -ting  the 
intruder,  and  is  able  to  inflict  a  serious,  painful  wound,  accompanied 
by  nausea,  headache,  fever,  and  even  temporary  paralysis.  Fortu- 
nately, the  cotton  ant  is  able,  by  its  superior  dexterity,  to  defend 
itself,  and  is  always  victorious  in  a  struggle  with  the  harmful  Texan 
species,  the  extermination  of  which  would  be  almost  as  welcome  at 
Victoria  as  the  destruction  of  the  boll  weevil  itself. 

The  Indians  believe  that  the  keleps  are  able  to  combat  also  the 
dreaded  teken  or  leaf-cutting  ants  which  are  as  serious  pests  in  Guate- 
mala as  in  southern  Texas.  It  is  scarcely  to  be  supposed,  perhaps, 
that  they  can  drive  out  well-established  communities  of  the  leaf -cutters, 
but  they  may  prevent  the  growth  of  new  colonies  by  killing  the 
workers  as  fast  as  they  appear  above  ground.  At  least  there  are  no 
nests  of  leaf-cutters  in  the  areas  occupied  by  the  keleps. 

The  fact  that  the  ants  were  fed  on  sugar  during  the  journey  from 
Guatemala  to  Texas  has  suggested  to  some  planter-  that  the  insects 
may  escape  from  the  cotton  plants  and  attack  cane.  This  apprehen- 
sion is  also  quite  unnecessary.  The  moistened  sugar  was  used  merely 
as  the  most  readily  obtainable  substitute  for  the  nectar  secreted  for 
the  ants  by  the  cotton  plant.  The  ant's  jaws  are  especially  adapted 
for  catching  the  weevils  or  other  insects,  but  are  quite  unsuited  for 
pmawing  into  sugar  cane  or  other  vegetable  tissue-.  They  are  too 
long,  blunt,  and  weak  to  be  effective  for  biting,  and  are  used  only  for 
seizing,  carrying,  and  pulling  apart  their  prey.  They  do  not  crush 
nor  chew  their  food,  and  are  apparently  unable  to  eat  anything  except 
liquids  or  substances  soft  enough  to  be  lapped  up.  as  it  were,  by  their 
tongues.  While  the  insects  are  feeding,  their  jaw-  are  usually  opened 
wide  as  though  to  get  them  out  of  the  way.  The  strong  front  legs 
are  used  in  much  the  same  manner  as  the  squirrel'-  paw-,  to  assist  the 
jaws  in  grasping  and  turning  the  prey,  though  they  serve  also  for 
walking. 

None  of  the  numerous  varieties  of  cotton  growing  at  Victoria  has 
nectaries  equal  in  size  to  those  of  the  Guatemalan  cotton  protected  by 
the  ant-,  but  the  quantity  of  liquid  food  available  in  fields  of  such 
varieties  as  King  and  Parker  may  prove  sufficient,  the  average  size  of 
cotton  plants  in  Texas  being  much  larger  than  in  Guatemala.     More 


14 

ants  \n  i  1 1  be  necessary,  however,  for  their  protection,  and  the  nectar- 
producing  qualities  of  the  different  varieties  may  become  a  question 
of  practical  Importance  if  the  kelepe  should  become  established.  At 
present  the  nectar  secreted  on  tin-  leaves  and  "squares"  of  the  cotton 
goes  to  waste,  or  even  serves  to  attract  injurious  insects,  among  them 
the  bollworm  moth.  The  discovery  of  the  ant  supplies  a  practical 
reason  lor  the  existence  of  the  nectaries,  hitherto  quite  unsuspected, 
and  it  suggests  the  further  possibility  that  the  weevil  and  the  ant  may 
have  been  factors  in  the  evolution  of  the  cotton  plant,  for  the  weevil 
i-  not  known  to  (vvd  on  any  plant  except  cotton. 

'l'he  former  report  alludes  to  the  scarcity  of  insects  in  the  cotton 
fields  protected  by  the  keleps,  hut  it  had  not  at  that  time  been  ascer- 
tained that  these  ants  were  a  cause  of  the  deficiency.  The  finding  of 
the  hone  yards  filled  with  the  disjointed  remains  of  their  prey  proves 
t  hat  t  hey  capture  and  con-nine  adult  insects  of  many  and  diverse  kinds, 
and  at  Victoria  they  have  shown  a  taste  for  bollworms  also  and  similar 
soft-bodied  larvae.  Their  appetites  are  not,  however,  without  dis- 
crimination. They  have  spared,  for  example,  the  lame  of  ladybirds, 
which  are  beneficial  insects;  also  those  of  the  small  Thecla  butterfly, 
which  is  sometimes  injurious  to  cotton.  The  former  are  often  picked 
up  by  the  keleps  hut  are  put  down  again  without  injury,  while  the 
latter  are  fondled  and  licked  with  the  tongue.  The  keleps  sometimes 
\i-it  plant-lice  and  leaf-hoppers  to  secure  honeydew,  but  they  have 
not  been  detected  in  taking  care  of  these  insects  or  in  carrying  them 
about,  as  do  many  other  ants.  This  is  the  only  suggestion  of  an  unde- 
sirable propensity  on  the  pari  of  the  keleps,  but  the  danger,  if  any.  is 
extremely  remote — much  less,  indeed,  than  with  many  ants  native  in 
the  United  State-. 

Bl    MMAKY. 

The  present  status  of  the  investigation  of  the  boll-weevil  ant  may  be 
summarized  by  saying  that  three  of  five  crucial  questions  have  been 
met  and  answered,  and  that  two  others  are  still  to  he  reached,  but  with 
no  insurmountable  obstacles  a-  yet  in  sight. 

(1)  An  ant  has  been  discovered  in  Guatemala  which  attacks  and  kills 
the  adult  boll  weevil,  and  thus  holds  this  most  injurious  insect  in  check 
and  permits  the  regular  harvesting  of  a  crop  of  cotton,  even  under  con- 
ditions favorable  to  the  weevil. 

(2)  This  ant  is  carnivorous  and  predaceous;  it  injures  no  form  of  veg- 
etation, and  takes  nothing  from  the  cotton  plant  except  the  nectar  secreted 
for  it  on  the  leaves  and  floral  envelopes. 

The  habits  and  temperament  of  the  insect  are  such  that  it  is  readily 
kbit  of  domestication,  transportation,  and  colonization  in  the  cotton 
tields  of  Texas. 


15 

The  issues  which  remain  to  l>e  determined  are: 

(4)  Whether  the  keleps  will  survive  the  winter  climate  of  Texas ;  and, 

(5)  Whether  they  can  be  obtained  or  propagated  in  sufficient  numbers 
to  serve  the  practical  purpose  for  which  they  have  been  introduced. 

It  would  be  most  unfortunate,  however,  if  the  discovery  of  what  may 
prove  to  be  an  effective  enemy  of  the  boll  weevil  should  result  in  any 
premature  relaxation  of  efforts  to  avoid  damage  by  cultural  expedients. 
Indeed,  it  seems  quite  possible  that  the  first  use  of  the  ant  may  be  to 
render  such  measures  more  effective,  since  while  still  limited  to  small 
areas  the  keleps  may  be  able  to  perform  an  important  service  if  they  can 
still  further  reduce  the  number  of  weevils  which  survive  the  winter.  If 
the  cotton  plants  close  about  the  nests  of  the  ants  were  allowed  to  remain 
through  the  winter,  the  weevils  would  congregate  upon  them  and  thus 
furnish  the  food  which  the  ants  are  likely  to  require  on  warm  days  of  the 
colder  months. 

o 


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